Side discharge grate for batch sintering machines



Filed July 19,

1 w. KELSEY 2,571,582

SIDE DISCHARGE GRATE FOR BATCH SINTERING MACHINES 1949 y 3 Sheets-Sheet l f .III Illlhlll 33A BY @WW W. KELSEY Oct. 16, 1951 2,571,582

SIDE DISCHARGE @RATE FOR BATCH SINTERING MACHINES 3 Sheets-Sheet 2 Filed July I9, 1949 W v J W. KELSEY I oct. 16, 1951 SIDE DISCHARGE GRATE FOR BATCH SNTERING MACHINES ggg/ ZZ-2.15 @if f WV W/ INVENTOR.

is 47m/MH Patented Oct. 16, 1.951

UNITED srATs-s PATENT oFF-ics SIDEDISCHARGE GRATEJFOBIBATCH SNTERING MACHNE'S 'WalterKelsey, New York, N.`Y.

Application Julyr19, l949,.fSerial?No.05571 (Cl. '26S-421) Claims. l

This invention relates to a side discharge :grate forbatch Ysintering machines, `in which the sinter cake is moved laterally fronrover the grate ytothe broken at a point distantfrom the grate.

One of the objections .in the use of the grates as heretofore pro'posedwas that the vsinter Would cake on the top of Vthe grate bars and sometimes in the Vspacesbetween the bars, so 4that upon the attempted movement of the sinter cake in Aits frame laterally away from ;thefgrate,v.a resistance was encountered'A preventing a Apracticaland.workmanlike operation.

vTo overcome these .and other objections, to tthe grates as 'heretofore proposed, the Atop of Vthe improvedgrate is vcomposed of bars oplaced `on edge 4and spaced to give the required air .passages, with the top edges as Aa whole .xedJand aligned with the discharging motion of thelsinter cake frame. This smoothtop surfacelpermitsa sliding of the sinter cake, While in the framefif there is no cohesion'between the bars and the sinter. To remove such cohesion, the :top .of Jthe bars, Awhile 'heldin a fixed place, are given a reckingmotion to -tilt their upper surfaces, order to :break any burned connection `of the sinter cake to the grate, providing a shearing area or zone and doing this without movingthe sinter cake. The grate bars .arelmade in .1s-mall abutting sections fitted and tied together-inline forming groups running ythe Width of the grate, these groups being assembled parallel Witheach other and properly spaced `to cover the `whole grate area.

Parts are mostly foundry made .and any bar can be removed and replaced Without disturbing other bars. The grate is designed to give a reasonable life and operation and can be installed ata reasonable cost. Thus, a fixed .grate is '.provided on which materials can be sintered, this grate being operable eto-breakthe burned bond between the sinter cake and the .top of the .gr-ate, enabling the sinter cake to be V'discharged Aor shoved from above the grateto one side :of the grate, without difficulty.

The invention nds its embodiment inthe. combination of a plurality of spaced gratebarsrfor supporting thesintercake, each grate bar having a substantially flat top surface .and Va Wedge shaped body converging to its narrower bottom surface, the vvertical dimension `of Vthe 'barzbeing longer than lthe width of ithe flat top surface, with fixed oscillating centers, one for each grate bar and disposed near the top surface of :the bars, and means for oscillating the lower end of the bars, whereby relatively large .movements of the bottom of the grate bars tilt the top surfaces of `the :grate bars va relatively small .distance suicient ,for "separating'the flat top surfacesf the grate bars .from the bottom of the `sinter cake by breaking the burnt comiection.

The invention includes an improvement :inthe impervious-strip between thegrate and the-walls surrounding the grate, which strip as 4improved is made upof abutting :loosely att-achedind-ividual members. lThe invention includes also, .afspacing strip'at the top of vthe grate bars having circular contours-spaced along `its length in which `:portions of the grate bars having the same contour t, :being :held by .brackets Aand .tie-rods. Also, a link engaging the lower part of the inotched grate hars, to :oscillatethe :same for use. .'Also, in a heat compensating device, `at one or two opposite sideszof the grate., to allow YfortheeX- pansionor contractionxof vthe grate .asia `whole. And 'nally,.in a specific .form of `such :compensating device.

:The invention will ybe more fully .described hereinafter, yembodiments thereof shown .zin vthe drawings, andtheI invention will lbe finally 4pointed out inthe claims.

.In the accompanying drawings,

'Figure lisaplan view of the improvedfgra'te;

Figure 2 a vertical section on vline .2 5-2.1of Eig. fll;

'Figures isa vertical ysecticncn.li.ne .3+i1;of Fig. y1;

Figure =.4 is an enlargedsectional view .cfa few of the grate bars and the .means for 4tilting'zthe samewith:a:compensating spring device to allow for `heat expansion and contraction;

Hligure 5,-is ka section taken on line5--5 offFig. 4;

.Figure 6 isa vertical plan view taken fromfline ii-E-lof Fig. Lishovving .the spring'only;

:Figure '7 is abroken side view yof a grate .bar showingthe bottom notches and roundedends atithe top;

Figure "la .isga topzview of Fig. '7;

'Figure 8 is a bottom view of. Figi?, lookingup;

lf-figure i9 is a vertical section of. a grate -bar takenxon 1ine.9-9:of Fig. 9a;

Figure 9a is `abroken side View Yof Fig.A 9;

:Figure 10 .gis .aNertica'l isection. of Va gratebar having *al rounded top takencn line lill-1.0 of Fig. 10a;

Figure 10a is abroken `View of Vthe end bar over which the impervious strip rests;

Figure 11 isa detail .plan viewof a tooth .engaging .,link;

`Jiigure Vlla/is a section onlinelfla-Lllabf Fig. 1l;

Figure 12 is a. side view of the spacing and centering device for the grate bars;

Figure 12a is a section on line I2a-l2a of Fig. 12;

Figure 13 is a broken plan view of the end impervious strip at the end of the grate;

Figure 14 is a vertical section on line |4--I4 of Fig.13,'

Figure 15 is a vertical section on line l5-I5 of Fig. 13;

Figure 16 is a vertical section on line I6-l6 of Fig. 13;

Figure 1'1 is a broken plan view of another end impervious strip at the end of the grate;

Figure 18 is a vertical section on line I8-I8 of Fig. 1'1;

Figure 19 is a plan View of the bed plate at one end of the grate cn which the end impervious strips are disposed;

Figure 20 is a vertical section on line 20-20 of Fig. 19;

Figure 2l is a perspective view of the end impervious strip which rests on the bed plate;

Figure 22 is a sectional end view of the rear bed plate and rear impervious strip;

Figure 23 is a side View of Fig. 22;

Figure 24 is a sectional View of the front bed plate piece;

Figure 25 is a sectional view of the end bed plate piece;

Figure 26 is a plan view of an impervious piece of the front impervious strip tied to the front bed plate;

Figure 27 is a vertical section on line 21-21 of Fig. 26; and

Figure 28 is a side view of an alternate form of the compensating device, of Fig. 4, to allow for expansion and contraction of the grate.

Similar characters of reference indicate corresponding parts throughout the various views.

Referring to the drawings, the grate is shown in plan in Fig, 1 within the one piece sinter frame and in section in Figs. 2 and 3, with the sinter frame 59, 59A, 6I and 60, above the grate. The sinter charge is placed on the grate and held in place by the end walls 59 and 59A of a known construction, and between the front side wall 60 and the rear or back side wall 6I (Fig. 2). The walls 59, 59A, 60 and 6I are moved with the finished sinter cake from above the grate to a position away from the grate. After the sinter in the sinter frame has been completed, the frame may be moved completely away from the top of the grate, to a position where the sinter cake may be broken away from the frame, and thereafter the empty sinter frame is again placed over the grate. The sinter frame is then lled, and the contents are sintered. Generally, referring to Fig. 2, the sinter frame with its contents is moved horizontally from right to left of Fig. 2, untilthe end 60 is above the supporting wall 51. And thereafter, the empty frame is returned to the position shown in Fig. 2.

The grate bar unit is preferably wedge-shaped set on edge, wide edge up, and made short to minimize heat distortion. This wide bar top edge is smooth and straight without indentations on top or sides. A grate bar group runs the width of the grate between the impervious strips 42 and 41 (Fig. 2) and is composed of center pieces 35 and end pieces 36 and 36A. At the top of and above each joint of abutting ends or supports of the pieces 35, 36 and 36A, is a rectangular spacing strip 38 (Figs. 1, 2, 3, 4 and 5), set into the top of the grate bar and depressed below the level of the top of the grate bar. This spacing strip 38 is toothed to t the spacing of the grate bars and 'between and at the root of each tooth is a half circular space to t the top of each grate bar at the end supports or over the -center supports taking the top of two abutting and joined grate bars 35 and 35. The teeth on the spacing strips are shorter than the width of the top of the strip to prevent to some extent the ne sinter from getting under the teeth. These spacing strips 38 are made in workable lengths, butted together, and are held down in place by the rod ties 33 (Fig. 2), suitably placed connecting through the hole 38A (Figs. 5 and 12) and attached to brackets 33A on stationary supporting beams 55. These ties 33 span the oscillating T 50, (Fig. 2). This spacing strip 38 extends from end to end of the grate, one end abutting on the impervious piece 4I and the other end on the end-closing impervious pieces 39 or 49, held in place by springs 48 and 49 (Figs. 4 and 6). This spacing strip is fixed and holds each grate bar in a xed position at the rocking center 38C (Figs. 4 and 12) of the semi-circular space between the teeth.

The lower part of each grate bar at an end or bearing rests on a T or bar 50 (Fig. 4, said lower part), and is held in a link 5l (Fig. 11) which oscillates with the bar 50 below the xed point 38C giving the top of each grate bar at G (Fig. 4), a rocking and slightly oscillating or tilting motion in order to break the burned connection between the tops of the grate bars and the sinter cake without displacing or moving the sinter cake. This breaking of the burned connection between sinter cake and grate reduces greatly the power required to start the movement of the sinter cake in its frame. The said rocking motion of the grate bars is used only at the completion of the sintering and at the beginning of the discharge movement of the sinter frame. At other times, the grate bars are stationary.

Grate bar pieces 34 (Figs, 1 and 10), are the same as pieces 35 (Fig. 1), except that the top of central part of piece 34 is cut down to rounded top ends N and supports the end closing piece 39 (Fig. 1). The grate bar pieces 31 and 31A (Fig. 1), are the same as pieces 36 and 36A (Fig. l), except that the top of the central part of each piece is cut down to the rounded ends N and to take the end closing pieces 40 (Figs. l and 4).

The space from the top of each grate bar to the top of the supporting bar 50 is the same for all bars, except those with the rounded tops, giving, with the grate bars in vertical position, a level grate surface. Each group of grate bars is assembled with the surface H (Fig. 9a) of pieces 36 in contact with the impervious spacing bar 42 attached to the bed plate pieces 45 (Fig. 2). The pull of the sliding sinter cake longitudinally aligned with the grate bars will keep the groups of bars in position.

The temperature of the gases passing through the grate will vary greatly and allowance is made for the expansion and contraction of parts of the grate or the grate as a whole. With the spacing strip 38 abutting against the xed impervious piece 4I, allowance is made at the opposite nominally fixed end of the grate for any expansion. This nominally xed end of the spacing strip contacts with the impervious piece 40 (Fig. 4) which rests on the bearing plate piece 44, (Figs. 3 and 4). With a short grate, as shown in these drawings, a single spring, as 48 (Fig. 6) can be made to take up all the motion and hold all the bars in the desired approximately upimpervious spacer pieces 41 senese right l'p'osition. =0n`efsend Lof the spring i's fixed and one end is movable, fthe movable :end fbeing secured to the piece 4i). The supporting member 50 iisalsoaiectedabyxthelheat. To minimize distortio'nidue-to heat in-this pieceiitccan be made :in .short #sections .connected together endto-endbyflexible 'joints v(not shown). A `roller bearing 54 is to `be --placed ateach end of feach short section so that uneven loading. on the grate will noty displace A-any part ofi theH grate.

The roller bearings, not shown, lare in the bearing housing -54 which is shown -only Aas -the inclosure lhousing and the designation lmark 154 is'hereinused rto includelthe-roller feature. (Fig. 3.)

:In `theshort Vgrate, as "here'shown, the 'operating shaft52 f(-Fig.3) placedI-atvtheendopposite the end having'the springf48. The action of the --supporting .member 50 from theapplication of the heat will be Yabouti-the same as the actionfon the spacing strip 38. Piece 59 is-held at the operating shaft 52 and -the other end is free. With -a long grate, the operating-shaft 52 would be `placed `near the center with the supporting member v'.50 held at the shaft with both-ends free. iIn this case, springs lWou-ld be used at each'end, the light-spring -48 (Fig. 6), restrained Vby a ltie VA48A (Fig. 4), to keep Ithe bars vertical Vand centered. -As expansion increasesfa heavier spring -49 (Fig. 6), restrained by tie 49A(Fig.4), will come into'acti'onto keep the bars vertical and centered. Athird, still heavier restrainedsprngmay be used if necessary. This spring location at the underside of the grate is convenient. In case the hot gases act unfavorably on the springs, they can be replaced by weights or springs away from the gases and the action conveyed tothe restrainingrpiece 40 by suitable linkage.

A linkage for holding y.the spacing strips 38 in place by its action through the restraining piece 413 is shown in Fig. 28. The lever Gis .pivoted at'69'on'the'support'1l and acts o'n the restraining piece vll'dat the leverend 1B. The weighton line 62 is divided by the adjusting lever '-63 part "of the YWeight `J'ti'ein'g directly Vby tie 65`to restraining'pi'ece "40tohold that piece in place and part tieing by tie 64 to the point 61 placing that part of the weight so as to act on the lever 6E. This latter part of the weight brings the required pressure on the restraining piece 4l) at lever end 1S. The action of the expanding spacing strip 38 is to move the lever end 153 against this pressure and raise the other weighted lever end at 61 along the arc 68 With pivot 69 as a center. This motion increases the eiiective lever arm between point 69 and point E1 and increases the pressure exerted by lever end 1li on the restraining piece 40. With identical weights and levers at each end of a grate and the spacing strip free to move as it expands by heat, the spacing strip will be held central under all heat conditions as the pressure at each end will be equal. Friction will be the only disturbing element in this combined and opposing lever action and that can be kept at a minimum.

The grate bars extending from side to side of the grate are also affected by the heat. The end bars 36 will rest against the bolted down impervious spacing bars 42 (Fig. 2) with an opening allowing for expansion made at the opposite or.. front end. This opening is covered by (Fig. 2). This spacer piece 41 (Figs. 2, 26 and 27), is bolted down and held in place by hooks K engaging the short-.sections .ofi bearing :.barsrM .f @Eigsmh which are part'iofzaflbed :plate 46 (Fig-2).. :The-expansion nf tthe parts-'of group of :grate I.barsisirallowedi Vfor :by fthe-sliding llengthwise .of A.the` rollers in the bearings 54 under theipiecesill.`

vThe oscillating apiece '.orT 156 rests on roller bearings-54 (Fig. 2) (in'dicated'by housingonly), which .are supported :on l.the grate :supporting beams 155. The operating shaft 52 (Fig. 3) .is connected through :suitable k,arm .and .bearing i5?. (indicated only). This shaft .is zsupported .by bearings :(not shown) rand Agiven 1.a frotary rrecipro'cating motion Vrthrough .power connections (not shown) This .grate iis surrounded 'by .four Vbed'fplates 4Sand1f44 (Fig. 3.),.and'45 and`46 (Fig. .2). YVThe two tend ,walls `5.9 .and .59A rand the front -wall tand'rear walll constituting the .rsintenfr'ame are vsupported Lon these bed plates. Wall 6l directly on a bed plate, Vandthe `other'walls (Si), 59-: and -5f9A) rest* on :bearing p-bar 1M andwb'earing plates 1413A and 44A. The walls .-59-and^59A have wearingfpl-ates 52B secured thereto. Thei'bearing banM is secured to the bed fplate f-45.; and gth'e bearing plates 43A and '44A are secured -tc vtheir respective bed plates. These bedplates lareanchored in' place on :the structure vor foundation, anchor bolts and .grout holes not being shown. Bolting for lthe impervious `pieces 4.1 and i l2/:are notshown. Abolt^-hole'1-32 for-the holdingdcnvn lbolts for piece l'41 iszshown. Bed plate43,\yvith impervious; piece 4l isusedffati one end of f av short grate with .thel operatinglshafti 52 located :at the same end. At the opposite-endr-of a Vshort-grate, bedLplate '44. (.Figs.13:and-4) is` provided, tolwhich one Vend of-faicompensating springris secured, lwith thelother endtof .the spring movable 'itvjith `the piece 4t. The operatingifshaft52 .is1pla'cedzalt the center .of along grate and :compensating .de- Vices-ifarezplacediat:both'lends Pieces 3.9 andv4'il are .placed endete-.end and ylocked at l) .against any endsuplitt. (Figs. 1:3 4and 17;)

LThe inneredge of eachimpervious -stripin conta'ct'with the grate will be subjected to the full application :and temperature fluctuation :iof .the heated gases, and this heat action would soon distort and break the .icastingsif .theffimpervious edges were made in one 'piece'iwith ithe 'several bed plates. To avoid this, the inner edge of or the whole of these impervious strips are made of short sections or pieces so loosely attached to the bed plates that distortion, due to heat, will not be carried back into the bed plates. These pieces are 4I (Fig. 21) connected to bed plate 43 (Fig. 3), 39 and 40 connected but free to slide on bed plate 44 (Figs. 3 and 4), 42 connected to bed plate 45 (Fig. 2), and piece 41. Pieces 41 are held down by bolts (not shown), passing through the openings 32 in the pieces 41 and through the openings 32A of the bed plate 46 (Figs. 24, 26 and 27).

I wish it to be understood that I do not desire to be limited to the exact details of construction shown and described, for obvious modications will occur to a person skilled in the art.

I claim:

1. In a side discharge grate for a batch sintering machine having a grate with four sides and a sinter frame over the grate having walls surrounding the grate, the combination of an impervious strip along each of the four sides of the grate, between each side of the grate and the adjacent surrounding Wall .of the sinter frame, said grate being composed of groups of grate bars abutting end to end and extending over the whole surface included between the said impervious strips, the tops of the said grate bars being horizontal and level, and the tops of the said impervious strips being level with the tops of the said grate bars.

2. In a side discharge grate for a. batch sintering machine, the combination of a sinter frame, a grate, said grate being composed of groups of grate bars abutting end to end and extending between each side of the grate space, parallel rows of groups of such grate bars extending the length of the grate space. the top of each of the grate bars being horizontal and free to tilt, oscillating centers for said grate bars spaced and held in Iixed places, toothed spacing strips for spacing the centers of oscillation, means for supporting the grate bars, means on said supporting means engaging the bottom of the said grate bars, and means for oscillating the said grate bar supporting means.

3. The structure of claim 2, including the combination of a toothed spacing strip having spaced teeth, the space between two teeth being semicircular, said teeth having a narrowed extension of a thickness lessl than at the semicircular part, the length of the tooth being less than the width of the spacing strip, and grate bars having ends abutting each other, said spacing strip iitting over the abutting and terminal ends of grate bars with said grate bar ends being tted to the semicircular parts of the said spacing strip with the top of the said spacing strip when assembled with the grate bars below the level of the top of the grate bars.

4. The structure of claim 2, including the combination of a grate bar supporting bar, an elongated link on the top of and attached to said supporting bar, the long link axis extending across said supporting bar providing spaces at each side of the bar, and a grate bar having notches, said notches being engaged by the link, and the projection between the notches being within the link, said grate bar being formed of abutting members each of which has a projection, the link holding the abutting members together.

5. The structure of claim 2, including a supporting beam parallel with the spacing strip, a

bracket on the beam, and means connecting the' spacing strip to the bracket.

6. The structure of claim 2, including the combination of a plurality of lsupporting beams, brackets attached to the supporting beams engaging the beams, and tie rods connecting the brackets and the spacing strips, said brackets and tie rods being located and spaced at suitable intervals.

7. The structure of claim 2, including the combination of a movable member at one end of the same normally pressing against said spacing strip, and a movable pressure lmeans acting on said movable member to permit the expansion and contraction of said spacing strip.

8. The structure of claim 2, including a, plurality of oscillating supports, the top of said grate bars being held in fixed position by said toothed spacing strips, means for holding said strips, said means including a weight operated lever, and an arm on said lever exerting a pressure on the strips, the weight carrying arm of said lever beingr so placed that with any motion of the lever by said strips, the effective length of the weight arm will be changed.

9. The structure of claim 2, including the combination of an impervious strip along each of the sides of the grate, said impervious strip being composed of a plurality of separate pieces abutting end and end and individually replaceable, and bed plates for supporting said pieces.

10. The structure of claim 2, in which the oscillating means support the entire weight of the grate bars.

WALTER KELSEY.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 1,164,761 Simmons Dec. 21, 1915 1,388,335 Greenawalt Aug. 23, 1921 1,391,124 Krom Sept. 20, 1921 1,617,561 Alexovits Feb. 15, 1927 1,784,658 DeSamsonow Dec. 9, 1930 

